Circuit restorer



Marcfi 31, 1 953 QUINN 2,633,513

CIRCUIT RESTORER Filed April 6. 1948 2 SHEETS-SHEET 1 I Figl.

TIME

- 30 TIMES NORM/9L ZURRENT Robert F Quinn,

by W

H i s Attorn ey.

March 31, 1953 R. F QUINN CIRCUIT RESTORER 2 SHEETSSHEET 2 Filed April 6. 1948 Fig.2.

OIL LEVEL m Imi .d II I Inventor; Robert F. Quinn,

His Attorney.

Patented Mar. 31, 1953 UNITED STATES PATENT OFFICE Robert RQuinn, Schenectady, N. Y, assignor to "General Electric Company, a corporation of New York ApplicationApril s, 1948, Serial M19340 Claims.

My invention relates'to circuit'interruptersand more particularly to operatingmechanisms for circuit breakers of the automatically operable rec'losing type. More specifically, my invention is an improvement on the operating mechanism disclosed in application Serial N0. 19,364. filed April 6, 1948, McCurry 'et al., which is "assigned to the assignee to whom this "application is assigned. In this McCurry 'et a1. application, a recloser is claimed wherein a main motivating means opens the contacts in response to operation of actuating means'whi'ch in turn is responsive to predetermined conditions of the controlled circuit, and wherein a time delay mechanism causes delay of closing operations and-of predetermined opening operations of the recloser during persistent faults. v My invention, furthermore, is related to appliqationSeria l No. 19,258, filed April 6, 194B,' now Patent No. 2619;- 562, dated November 25, 1952, Qp'pel et aland to application Serial No. 19,213, filed April 6, 1948, now Patent No. 2,59'7;024, May 20, 1952, Oppel, which are both assigned to the assignee to whom this applica'tionri's assigned. V} In these two applications, a recloser is claimed wherein collapsible means are utilized to interrelate the opening operations of the reclo'ser contacts with a timing mechanism so as to modify the time current characteristic of the recl'oser upon the occurrence of predetermined conditions of the controlled circuit.

In operating mechanisms for recl'o'sing circuit breakers of the type disclosed in the above-mentioned application of Mc'Curry et al. in which provision is made for both instantaneous and time-delayed opening'operations, it is possible that the time-delayed opening operations, though fully capable of 'proper functioning for moderately excessive fault currents, may be too prolonged where the magnitude of the fault current is of the order from, sayf2'0to'30 times the normal full-load rating of the device.

A principal object of my invention is 'theprovision of an operating mechanism for electric circuit reclosers "having improved time -current characteristics.

Another object of my invention is to provide an operating mechanism for reclosing circuit breakers which is capable of increasing the interrupting rating, of the device without increasing the physical size or normal current carrying capacity thereof. 7

A further object of my 'inventionis'to:provide a recl'osing circuit: breaker such as that disclosed in the above application of McCurryet "a1; which has greatly improved time current characteristics 2 without,interferingwith the normal sequence of operations for persistent fault conditions which eventually result in a fina1'lock-out or lockedclo's'ed operation.

Still another'object of my invention is the provision of a much faster time-delayed opening Where the fault current is of an exceptionally high magnitude while maintaining the same operating characteristics for relatively low fault currents. 7

Still another object of ,r'n'yfinvention is to retain the advantages to be derived from the use of recloser operating mechanism of the type disclosed in the above-mentionedapplication of McCurry et a1. and at the same time to provide such a'rneclian'is'm with means for substantially decreasing the time delay occurring "for certain preselected opening operations if the fault current happens to "be in excess of a predetermined relatively high value of the orderfof 20 or more times the normal rated current carrying capacity of the device. p 7

Further objects and advantages of my invention will become apparent as the following description proceeds and the features of novelty which characterize my invention will be pointed out with particularity' in the claims annexed to and forming apart of this specification.

For a better understanding of my invention, reference may behad to the accompanying drawings in which Fig. l is 'a family of curves showing the time delayed opening time current charac't'eristicso'f a reclosing circuit breaker embodyi'ng my invention as well as the time current characteristic 'curves of fuses which are coordinated with the recloser; Fig. 2 is an elevational View in section of a recloser embodying my invention; Fig. 3 is a schematic representation of the circuit incorporated in the 'recloser shown in Fig. 2 and in which Fig. 4 is an elevational view in section of asmalljportionof Fig. 2.

In electric distribution systems it is desirable to obtain the maximum protection possible per dollarof investment in protective equipment. Frequently it proves feasible in a particular distribu'tion system to combine automatically operable reclosing devices and fuses. Fuses may be inserted into the line between the source of power and the reclos'er and may also he placed in the line' betwee'ri the re'clos'er and the load.

With reference to Fig. 1, the dotted line curve pq represents a desirable time current curve for the recloser while the curve aib represents the time current characteristic of a reclosing device such as that disclosed inthe above-mentioned application of McCurry et al, The curves c, d,

and 6 represent the time current characteristics of fuses inserted in the line between the source of power and the particular reclosing device. The longer time characteristics of the fuses will delay the operation thereof until the recloser Will have had an opportunity to open the circuit. The curves f, g and h represent the time current characteristics of fuses inserted into the system at points between the load centers and the particular recloser. The shorter time characteristic of this latter group of fuses will permit a particular fuse to blow and thereby disconnect the faulted load center from the system without causing the recloser to operate.

It is apparent from Fig. 1 that the fuse characteristic curves c, d and e intersect the reclcser time-delayed characteristic curve az'b between points z and b. Conversely stated, a recloser having a time current characteristic such as cib would be too slow in opening with time delay where the fault current were excessively high say of the order of magnitude of 30 times the normal current rating of the recloser, for instance. "It is apparent that, in order to overcome this difficulty, the recloser time-delayed characteristic curve aib should be modified somewhat to decrease the time required for time-delayed opening operation for very high currents without necessarily changing the time required for timedelayed opening for lower fault currents.

In accordance with my invention, [I provide means for modifying the curve az'b by causing such curve to assume the shape cii and thereby I more nearly approximate the desirable curve Pq and also avoid the possibility of a failure of coordination between fuses having characteristics such as c, d, and e and the recloser when opening with time delay.

Referring now to Figs. 2 and 3, the circuit shown in Fig. 3 comprises a pair of main or interrupting contacts i and 2, a bridging member 3, and a main operating coil d for opening the circuit through the main contacts i and 2 by moving the bridging member 3 out of engagement with the main contacts. A relay coil 5 controls the opening of normally closed relay contacts 6 and '1. One end 8 and the other end 3 of the circuit shown in Fig. 3 are connected to the two terminals of the recloser, only one of which is shown in the drawings and which is designated by the numeral it. It will be seen that main op erating coil i is short circuited by relay contacts 6 and 1 during normal service conditions and that relay coil 5 carries line current when main or interrupting contacts t and 2 are engaged by bridging member 3. Thus excessive current will activate relay coil 5 which will open its contacts 6 and 1 thereby diverting full current through the main operating coil d which Will then cause the bridging member 3 to move out of engagement with contacts i and 2 to complete an interrupting operation. Terminal iii and the other terminal of the device, not shown, are both mounted within insulators such as it which are mounted into the cover plate 52 of the device by means of adapter elements i3 and M and by the bolts i5. The operating mechanism is completely enclosed within a metallic tank 56 which has an insulating lining 57 covering its inner surface. The tank it contains an insulating fluid such as oil. The cover i2 may be secured to the tank l6 by any suitable means such as by a plurality of bolts which are not shown. Formed into the flange if! of the tank i6 is a peripheral groove H). A gasket 25 is disposed within the groove also are constructed of insulating material.

4 l5 and bears against the flange 2! of the cover I2 to seal the tank and thereby to prevent the leakage of oil from within the tank [6 between. the engaging surfaces of the flanges l8 and 2|.

The circuit breaker may be supported on a distribution circuit pole or the like by means of suitable studs or bands, not shown, which are welded or otherwise secured to the outer surface of the tank Hi. It is evident from Fig. 2 that the operating mechanism embodying my invention depends from and is supported by the cover Thus it will be seen that the whole mechanism may be removed from the tank I6 by unbolting and lifting the cover upwardly.

For the purpose of supporting the mechanism, a substantially U-shaped supporting structure 25 is used whose base or bight portion 25 is secured by welding or otherwise to cover plate l2. Since Fig. 2 is a sectional view, the base portion 26 appears in section and the forward prong or side plate of the U does not appear. The lower edge of each side plate of the supporting structure 25 is flanged as at 36 and to which flange is bolted the supporting posts 27. Secured to the lower ends of the posts 2'! is the assembly generally indicated at 23. The assembly 23 includes a hori zontal metallic supporting plate 29 to which the supporting posts 27 are secured by anysuitable means such as the nuts 30. Secured to the supporting plate 29 by means of bolts such as 32 are a plurality of L-shaped members or angle lugs 3|. Secured to the L.-shaped members 3| are the laminated magnetic structures 33 and 34 which support the main operating coil winding 4 and the relay coil winding 5 respectively. Secured to the lower end of the laminations 33 and 3d are the angle members 31 having horizontal flanges 38. Secured to the angle members 31 there is shown another horizontal metallic supporting plate 39 which is bolted as at 40 to the flanges 33 of the angle members 3 The interrupting chamber generally indicated at 4| comprises a lower horizontal plate 42 constructed of insulating material and side walls 43 which The plate 32 depends from the plate 39 through the agency of bolts it which are screwed into insulating pillars d5 of which only one is shown. The main interrupting contacts i and 2 are disposed within the arcing chamber as and are supported on the bottom plate 42 thereof by means of terminal bolts 46 and 31. The bridging member 3 is secured to armature it by any semirigid construction which is adequate to achieve a wiping engagement and disengagement between the bridging member 3 and contacts I and 2. Suitably arranged oil expulsion ports i i2 are provided to allow pressure due to arcing to escape from the arcing chamber M. For the purpose of biasing the bridging member 3 and parts associated therewith toward the closed position, the compressional spring 49 is used.

The relay contacts 5 and 1 are operated by the mechanism generally indicated by the numeral 55 in such a way as to delay the opening of the contacts 6 and 7 until the armature 5i of the relay has been moved upwardly to a point near the end of its opening stroke for purposes which will become apparent as the description pro ceeds.

The mechanism 5!) incorporates the link 52 which is pivotally connected as at 53 to the relay armature 5i. The lower end of link 52 is pivoted at 54 to the member 55 which in turn is pivoted to a fixed fulcrum 56 secured to the teasers arcing chamber wall 43 or which maybe supp'or-ted in any-othersuitablemanner. It will be observed that the member55 -i's-constr'ucted with the projection 5'! extending along a portion of its upper edge and also that the member --55 is provided with an apertured projection '58 which servesas-a means'iorjmounting one end of the tension spring 59. Also pivotally mounted at 56 is a 'membertfi is an apertured projection-5i towhich is attached-the other end'of the spring 59. Member '60 is also provided with a projectio'n 52 which engages one end or the compression spring 63. The rn'ember '6Ilfisalso provided'with a projecting pin which engages a holding recess of the curved "hook ty'p'e latch member -65 which is mounted upor'i 'a i fixed pivot 66 which pivot may be --secured to the wall as of the arcing chamber. A 'torsio'n spring it serves to bias the'mer'n'ber 55'for 'rotation'in the counterclockwise direction against the pin -54 mounted on the member 55. It will-be obsei-ved thatthe edge surface 61 ofthe member Ell abuttingly engages the projection 51 onthe member 55. The contact arm 1 is pivotally mounted atEE and is provided with a recess 58 into which the projection 62 on the member 60 ismovable. lhe bottom of the recess 68 constitutes a'srnall platform upon which the'small compression spring 63 is supported. The contact arm I is also constructed with a recess 69 which cooperates with the projection '5! on the member 80 by affording only limited angular movement between these two members.

The operation of the latch-closed switch '50 is as follows: Whenever the relay coil 5 is sufficiently energized to impart upward movement to its armature 5!, the link 52 is elevated carrying with it the right hand end of the'member 55. This motion of member55 removes its projection 51 away from the surface 67 of the member 60, and, as the member 55 is rotated counterclockwise about the pivot 55, the spring 59 is elongated somewhat and an increased counterclockwise movement is thereby exerted on the member 60. Member 55 is prevented from rotating in -th'counterclockwise direction, however, for a short time due to the engagement of. its overhung pin 64 with the latching recess of the curved latch member 65, As the arm 52 continues rotating upwardly, the forwardlyprojecting pin 54 eventually engages the curved latch member 65 and causes-such member to be rotated in the'olockwise direction about its fixed pivot '55 to unlatch the pin 54. Accordingly the increased pull of tension spring'59 'will now causerapid counterclockwise rotatio'nof the member 59 about fixed pivot 56. This counterclockwise rotation of member 60 will cause the contact arml't'o be rotated counterclockwise duetothe engagement of' the projections! on the member 68 with the upper'edge of the recess 59 in the contact arm 7. In this way the contacts-6'and I arese'parated thereby removing the short circuit from around themain operatingcoil l'w-hich diversion causes the'whole fault current to flow through 0011 4 and thereby initiates'an opening operation of the bridging member 3.

When relay armature 5| is allowed to descend as will be more fully explained hereinafter, the link 52 moves downwardly thereby causing the member 55 to be rotated clockwise. Because the projection 51 on the member 55 again is in engagement with the surface 61 of the member 50, members 51 and'tn rotate clockwise in unison to theiri'reset position. "The projectio'n BI within recess 69 'on the members causes the contact arm I also to move -'clock-'wise with members 51 and about-the pivot 56 and eventuallycauses the-contact 1 to re-engage th'e contact 5. In the meantime thepin'lil on th'emember B0 will-have moved along the -"cu'rved "surface Y of the member 55 back to-its original latched position=as shown in Fig-2. The 'c'ontact pressurespring will help cushion the -reclosing switch par-ts after the contacts Hand l mak'e'contact.

lt -is apparent that the latch-closed switch 59 will maintain'thecontacts G and"? in-engagement during the initial po'rti'on of 'a circuit opening operation and will permit the "contacts to separate 'only after the reIay armature 5 I has I moved to a point very near-to the end of its stroke.

The timing mechanism embodied in my invention 5 is generally designated by the numeral 12' which mechanism' will now be described. The numeral 13 designates a fix'ed shaft which is supported-at the front rea'r by-depending side portions HI which are'formedintegrally with the downw'ar'dly extendin'g side i plates of the generally U-shaped supporting structure 25.

pointed "out above, only the rear one of these downwardly projectin'g arms is shownand is in broken lines "in the drawings. Rotatable about theshaft 1-3 is'a'ratchet wheel l5 which has notched or toothed-portions 'lfi and Tlabout its periphery and which also is provided with i the smooth or unnotched intermediate peripheral portions 18 and 1 9. Also 'rotatable about the shaft 13 is a gear wheel BIFWhOse-entire periphery is provided with -gear' teeth. Ratchet "wheel 15 andgear wheel 8il' are connected together by a spring mechanism, which 'will be described hereinafter, so that underce'rtain conditions they rotate in unison. Both the-ratchet wheel and the gear wheel are provided" with an arcuate slot ill for a purpose which will-be apparent as the descriptionproce'eds. secured-to the gear wheel 80 and rotatable about shaft l3-as' a-center point is a pulley=-82, which is shown only in Fig.4, onthe'periphe'ry of which is wound a flexible cord 83, oneend of which is afiixed to some point on the periphery of the pulley-82 and the other end of which is tied to the tension spring 54. The oppositeendof springtd isattached to aperture'85 in adownturnedportion of the supporting-plate 26. Thetension spring 8:1, as will be'evident from the drawings, is'adapted to exert a counterclockwise turning moment on the. gear wheel 80 and is for theLpurpose-ofresetting the ratchet and gearwheels aswill-be'morefully understood as the description proceeds.

The speed of rotation of 'ratchet wheel 7.5 and of gear wheel so isgoverned by an escapeznent mechanism which will now'be described. Secured to the downwardly extending sides of the supporting structure 25 having the base 26 is a shaft 95. Rotatable on shaft silisapinion ill, the teeth of which engage the teeth of the gear 8! at all times. Secured to thepinion 9| and rotatable therewith is a ratchet wheel 52 which cooperates with the oscillatory escapement verge member 93 which. is pivoted at its center point to the pin 94 which pin is secured to the supporting arms 25. Rotation of gear 8| will cause rotation of pinion 9|, ratchet wheel 92 and the inter action between the teeth of -the ratchet wheel 92 and the projections of the oscillatory verge member53 will afford awatch-type escapernent device havings. time-delaying action in a manner well known in the art.

In order to interrelate" the opening operations "of theren ermatureJi'a d theratchet wheel 'wtian'openingpaw1 96 -is'u'se'd. Pa'wl'fit' is pivotally mounted at 91 across the spaced arms of a U-shaped carrier member 98, which member is pivoted at 13. A torsional spring 99 is used to bias pawl 95 for rotation about pivot 91 in the clockwise direction so that, unless prevented from doing so, the pawl 96 will engage the periphery of the ratchet wheel 15. The carrier 98 is connected to the connecting link I by a pin IIlI which is interposed between and secured tothe front and rear arms of the U-shaped member 98 and which pin is adapted to ride in the arcuate slots 8i in both the ratchet wheel and the gear wheel. The lower end of the link I is pivotally connected to the armature 5| by any suitable means such as by the pin 35. I

In order to cause the pawl 95 to become disengaged from the periphery of the ratchet wheel 75 when the carrier member 98 is in the position shown in Fig. 2, a projection I82 is provided which is secured by any suitable means to a downwardly extending portion of one or both the sides of the U-shaped supporting structure 25.

For the purpose of interrelating the closing operations of the armature 48 and the ratchet wheel l5 and the gear wheel 253, a closing pawl IE5 is provided. Pawl I05 is pivotally mounted to arm Hit by any suitable means such as by a pin ml. The pawl m5 is biased for rotation about pivot pin it? in the clockwise direction by means of a torsional spring I58. Arm I55 is pivotally supported at its left hand end on the shaft "I3. In order to cause the pawl to disengage the periphery of the ratchet wheel 75 as is required during a circuit closing operation, a pin I89 is provided which is supported by a downwardly extending portion of one or both the sides of the supporting structure 25. A link H6 is connected at its upper end to the arm I58 by the pin Iii! and at its lower end a pivotable connection III serves to connect the link I I!) to the armature 4B which is disposed within the main opening coil 4.

For the purpose of automatically locking the interrupter contacts in the open position after the circuit breaker has performed a predetermined number of opening and closing operations, a linkage mechanism is provided which will now be described. An arm I I3 is rotatable about the fixed shaft 95 and is apertured at its upper end for connection to the tension spring II4 which biases the arm M3 for rotation in the clockwise direction. The arm I I5 is pivotally connected at its left hand end to the lower end of the arm I I3 by a pin I55. Arm H1 is pivotally connected to the right hand end of the arms H5 and I06 by a pivotal connection to the opening pawl pivot pin Idl. Arm i I7 is provided with a slot I IS through which the pin I I9 is slidable. Pin I I9 is mounted on an arm I22 which is pivoted at I2I to the supporting structure 25. A tension spring I22 is connected at its left hand end to the supporting structure 25 and at its right hand end to the pin i IS. A pin I23 is secured to the ratchet wheel "I5 and hence is rotatable therewith, the ratchet wheel functioning as a counting device to determine the number of operations of the recloser during a persistent fault. When the mechanism is operated so as eventually to advance the pin 23 from the normally closed position of the recloser as a result of several successive reclosures,

the arm H3 will be rotated slightly by the pin I23 in the counterclockwise direction about its supporting shaft 95 against the action of the tension spring II l. This action causes the link I I5 to be moved to the right, a suitable slot being provided in this link to permit this movement. Immediately following this motion to the right of link II5, link IID will be moved upwardly due to the final opening operation which will move the slotted link II'I upwardly. Movement to the right of link II5 together with upward motion of link Ilil causes the right-hand end of link II5 to collide with pin I I9. This collision will rotate the arm I20 in the counterclockwise direction about fixed pivot I2I. This movement of arm I23 will move the spring I22 over center. The spring I22 will cause substantial counterclockwise rotation of the arm I20 about its pivot I2I so that finally the pin IIB becomes effective to hold up the whole main switch movable structure in open-contact position by engaging the upper end of the slot H8 in IN. Prior to the collision of pin I23 and arm II3, the link H5 is rotated during opening and closing operations about pin I I8 with this pin in the position shown in Fig. 2. With pin IIB so located, link II5 clears the pin HQ and the mechanism is not locked open.

For the purpose of closing the main contacts after the breaker is locked-out and for the purpose of manually opening the main contacts, a bell-crank having an external arm I25 is provided which is pivoted to a fixed fulcrum I26. Opening I21 is incorporated in the right hand end of the arm I25 and an opening I28 is incorporated in the left hand or internal arm of the bell-crank. If the breaker is closed and if it is desired to manually open the breaker, a switch hook is manually inserted into the opening I21 and then pulled downwardly, thereby turning the bell-crank through a clockwise movement. Accordingly, when the lower edge of the opening I28 engages pin N9, the link N1, the link IIO, the armature 48, and the bridging member 3 are all elevated and hang from the pin H9 in the contact open position so that the device will remain locked-open by the open toggle position of spring I22 and toggle link I20 as described for the automatic lock-out procedure.

If the device is locked-open manually or automatically, in order thereafter to close the contacts, it is only necessary to elevate the right hand end of the arm I25 thereby rotating the bell-crank in a counterclockwise direction about its pivot 526 which action restores spring I22 and toggle link i20 to their stable normal overcenter position and permits the arm III, the arm III], the armature 38 and the bridging member 3 to be lowered to close the contacts under the action of biasing spring 49. In order to cover the opening in the cover I2 through which the arm I25 extends, a cowl I29 is provided.

It will be understood that the device could be adapted to perform, within limits, a relatively wide range of opening and closing operations wherein certain of these operations would be time-delayed and wherein certain others could be made to occur almost instantly. For persistent faults the particular device described above and shown in Fig. 2 is adapted to perform a first instantaneous opening operation followed by a time-delayed closing operation, a second instantaneous opening operation followed by a time-delayed closing operation, a third opening operation which is time-delayed followed by a third time-delayed closing operation, and a fourth opening operation which is time-delayed followed by a final lock-out operation.

Assuming that the interrupter is closed as shown in Fig. 2, a fault condition on the circuit 9: controlled by the device' will cause an excess amountof current to flow through the-relay coil 5 whichwill immediately cause-its armature 9i to'move upwardly; As the armature-5| moves clockwise about the shaft 13 and the opening upwardly, the U-shaped carrier 98 will 1 move pawl 96 willbecome disengaged from the projecting member 192. Torsional spring99thereupon will rotate-pawl 96 in the clockwise directioncausing the pawl toengage the smooth portion lg oi the ratchet wheel 15. Hence, pawl 98 will be free to-slide along theratchet wheelie without appreciable impediment, so that the armature 5i and partsassociated therewith will move substantially instantaneously in the upwarddirection. Near the end of the upper limit oftravel of the armature 5|, the contactslt and 1 will open-aspreviously explained, the short circuit around main operating coil 4 will thereby be removed and the main coil lwill be forced to carry the fullamount of the'fault current. This current will cause the armatur'e'48 to move rapidly upward against the bias of spring 49. Upward movement of armature 49"" will elevate the link I 10' and in turn cause the closing pawl N35 to move upwardly in a counterclockwise direction with respect to the ratchet wheel 15,. Bridging member 3 will move out of engagement with contacts I and 2 and the circuit will be interru'pted, thereby deenergizing coils 4 and 5' and terminating the upward force on their armatures. When this opening movement has progressed a slight distance, the pawl l95-will become disengaged from the stopl99 and the torsional spring 108 will rotate the pawl I95 in a clockwise direction about the pivot Hi1. This clockwise rotation of pawl I05 will cause the pawlto engage the smooth portion 19 of the ratchet wheel -for'a-1imited time. When the armature 48 has reached the limit of its upward travel, the pawl l05'wi1l engage the toothed section 1'! of the ratchet wheel 15; The bias' of spring 49 together with the weight of the parts will automatically cause'the armature 48, the bridging member 9, the connecting link I0, pawl I05 and armature I I5 to move downwardly. Because the pawl I05 now is in engagement with the toothed section 11 of the ratchet wheel 15, downward motion of pawl I05 will cause clockwise rotation of the ratchet wheel 15' and the gear wheel 80 to which it is-coupled.' Rotation of g'earwheel will rotate the timerratchet wheel 92 through the pinion Bland time-delay will be achieved by the-oscillatory motion of the verge or escapement member 93 about the perimeter of the ratchet wheel 92-; Thus, the-closing operation of the device will be time-delayed'so'that the interruptingv contacts are maintained open for apredetermined short period of time. If the fault condition should havecleared itself, the bridging member 3 willremainin engagement with -the-contacts l and 2 and the ratchetwheel 15 and the gear wheel 80 will'be rotated-in a counterclockwise direction; to the; reset position as shown in- Fig. 2--by;the action of spring 84 and flexible cord 83-which reels offthepulley 82;

Should the fault persist, however, another opening operationwill be initiated; The smooth portion-78 of the ratchet-wheel 'l5' is sufficientlyv long; to afior'd no oppositionto upward opening movement of the'openiiig .pawl' 9 5 during the: second-:op'ening operation. 'I-he device; therefore, will open substantially instantaneously aspreviously-described andwill reclose with time-delay as already described since the' closing pawl 95 10 willstill be operating on thenotchedsection 1-! of the ratchet wheel. 7 V v Should the fault conditionpersist after the second reclosing operation, the relay coil 5- then will elevate its armature 5| but at a slower rate than before because the preceding two timedelayed reclosing operations will have beensuilicient to advance the ratchet wheel 'l5-in a clockwise direction to a point where the notched portion 16 of theratchet wheel 15 willbe-presented for engagement with the opening pawl 96. Accordingly, upward motion oi -armature- 5|, connecting link H99, arm- 98 and pawl: 96=- will cause the ratchet wheel l5 and the gear wheel to rotate in a clockwise direction Lhis clock.- wise-rotation-rotates the timer ratchet wheel 92 through the pinion 9i and, as previously ex plained for the reclosing operation, time-delay will be achieved through the oscillatory action of the escapementmember 93 whereby theinterrupting contacts now are maintainedclosedfior a short period of time. When the armature 5-! has reached a point near the end of its upward travel, the relay contacts 6 and 1 willbe opened as previously described and main-coil 4;willbe efiectively energized thereby elevating bridging member 3- to open the circuit. The two reclosing operations performed with time-delay. and the one opening time-delayed operation thus far described will not have been sufiicient to advance the notched section TI of the ratchet wheel 15 beyond the closing pawl I05 and so the pawl I05 again will engage the notched section of wheel 15 and cause the main contacts to close once more with time-delay as previously described.

Should the fault still persist, the interrupter will open with time-delay as described above in connection with the third opening operation since theopening pawl 96 will still be in a, position to engage the advanced toothed-section 16 of the ratchet wheel 15. Upon completion of this fourth and final openingoperation, the pin I23 will have been advanced from its initial position shown in Fig. 2 to the regionwhereit encounters arm H9 of the look-out linkage whereby the toggle arm I20 is rotated up. from over-center with respect to spring 122 to achieve finallock-out as already described. Briefly. restated, the engagement of the pin l2 3-with the arm H3- causes a slightcounterclockwise rotation of the'arm H9 about its fixed supporting pin which operation, when followed by an interrupting contact opening. operation which elevates the armature 48, the link- H0, and; the link H1 upwardly, will now produce interference between the outer end of-laterallydisplacedtripping link l'l5rand the projecting pin I I9 whereby. to-rotatethetoggle link Q20 toward its lockedout position. Obviously, the force of. the holdopen-spring I22 is sufilcient' to overcome: the force of-thecontactclosing spring. 49.

It may be perceived that the device can be converted from a locked-open device as above described'to a locked-closed device. For this purpose itis onlyv necessary to dispose a fixed pin on any fixed structure, such as the supporting structure 26, in sucha position that it will engagea pindisposed on-the ratchet wheel 15 so that immediately after the device has performed the desired-number of opening'andclosing operations, the pin on theratchet wheel will engage the fixed stop so as to prevent upward motion of the armature 5i (and parts associated there'- with) through the agency of the' opening pawl 96, thereby preventing the opening of the contacts 6 and I so that consequently the interrupting contacts are maintained closed. In this way a fault condition on the circuit is forced to either burn itself off or to blow an appropriate fuse or, in the event of fuse failure, to trip a station breaker.

The recloser so far described is not my invention but rather is as disclosed in the aforementioned application Serial No. 19,364, filed April 6, 1948, McCurry et al.

In accordance with my invention, I have provided resilient or collapsible coupling means for permitting the ratchet wheel 15 to rotate somewhat independently of the gear wheel 80 when the opening pawl 96 is in engagement with the toothed section of the ratchet wheel "I5, whenever the fault current is in excess of a predetermined relatively large value. As is more clearly shown in Fig. 4, I secure to the gear wheel Ill a stud I39 and I secure to the ratchet wheel I a stud I3I. Mounted about the shaft I3 and secured at the end portions thereof to the studs I30 and HI is a spiral spring I32, which spring is the only means interconnecting the gear 99 in driving relationship with the ratchet wheel '15.

With this arrangement it will be appreciated that while the gear 89 is still directly subject to the inertia or retarding effect of the timer escapement mechanism, the ratchet wheel now is subject to this timer control only through the intermediary of the spring I32. It will be clear that I may make the spring of any appropriate strength and that furthermore I can arrange suitable coacting stop members such as I33 on the ratchet and I34 on the gear for imparting a predetermined amount of preloading to the spring connection I32.

I choose the strength, gradient and preloading of the spring I32 so that, for overcurrents below a certain predetermined value, the spring functions substantially as a rigid connection whereby the ratchet wheel I5 is fully subject to the moderating influence of the timer mechanism as before. On the other hand, above this predetermined current value, the spring is collapsible so that the ratchet can be rotated with respect to gear wheel 80 and to a degree commensurate with the overcurrent; consequently, for timedelayed opening operations, the period which the relay contacts are maintained closed (by virtue of the opening pawl 96 engaging the ratchet wheel) is lessened not only due to the higher opening force transmitted to the timer mechanism which increases the oscillation rate but also because of the decreased amount of actual rotation imparted to the gear wheel 80 due to the virtual slippage the spring I32 has permitted between ratchet and gear up to the instant that the relay contacts have parted.

In the embodiment shown, the spring is strong enough to be deflected only in accordance with time-delayed opening operations; i. e., reclosing forces applied to the ratchet through the closing pawl I05 are not great enough to produce overtaking movement of the ratchet wheel I5 with respect to its associated gear 89.

The counterclockwise moment exerted on the ratchet wheel 15 due to the precharged spring I32 is of such a value that a time-delayed opening operation of the pawl 96, the link I09, the armature SI and the contact 'I will proceed with time-delay if the fault current on the line, and hence the force exerted by coil 5, is below a predetermined amount, in which case the gear wheel 12 7 B0 and associated time-delaying mechanism will be operated. Otherwise stated, the curve an of Fig. 1 will coincide with the curve azb of Fig. l in so far as the common portion on of these two curves is concerned.

If, however, the fault current is in excess of a predetermined value of the order of 20 to 30 times normal line current, the upward force ex erted by armature 5| through link I09 on pawl 98 will be sufficient to overcome very rapidly the counterclockwise moment exerted by the spring I32 on the ratchet wheel I5. The ratchet wheel, therefore, will be free to rotate in the clockwise direction without appreciable time-delay while the gear wheel 89 and the associated time-delaying mechanism will remain substantially stationary. Otherwise stated, the characteristic curve of the recloser will follow the line 27 rather than the line ii) and better coordination between the recloser and the fuses having the charac teristics c, d, and e as shown in Fig. 1 will be achieved.

It will also be apparent that the incremental angular displacement of the ratchet wheel 15, due to the rotation of the wheel by the closing pawl I 65 and by the opening pawl 96, will remain unaffected so that any predetermined sequence of opening and closing operations will proceed, as explained above, to a final lock-out or lock-closed condition of the device in just the same manner as formerly where the ratchet gear wheels were directly coupled together.

While I have shown and described a particular embodiment of my invention, it will be obvious to those skilled in the art that various changes and modifications may be made with out departing from my invention in its broader aspects and I, therefore, intend in the appended claims to cover all such changes and modifications as fall Within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is: v

1. An electric circuit reclosing device for performing a cycle of opening and closing operations and thereafter for automatically assuming a locked open position comprising relatively movable contacts, condition responsive means for operating said contacts, means for locking said contacts in the open circuit position, counting means adapted for incremental movement, means operatively connecting said counting means and said condition responsive means, said counting means being movable in response to op eration of said condition responsive means for causing operation of said means for locking said contacts in the open circuit position after a predetermined number of operations of said contacts, a timing mechanism, and yieldable biasing means normally biasing said counting means into engagement with said timing mechanism to cause said timing mechanism and said means adapted for incremental movement to move in unison to delay operation of said contacts during circuit closing operations and whenever the opening force developed by said means for operating said contacts is below a predetermined magnitude during preselected opening operations due to a fault condition, said yieldable biasing means being yieldable only in response to opening forces in excess of said predetermined mag nitude so as to cause relative movement between said timing mechanism and said means adapted for incremental movement.

2. An.operatingzmccbanisnrfor-anelectriczcincuita reclosing: device. having relatively-- movable contacts comprising; electromagnetic. means. re.- sponsive to fault-currents for opening-said. conetacts, means for imparting; closing-movementito said contacts, a timing mechanism, means. in:- cluding a rotatable member and. aprechargcd. collapsible member connected with; said. timing mechanism and disposed: in cooperative; relation to said electromagneticmeans ior'interrelating opening and closing operations of said contacts with said timing. mechanism, saidrot'atable member being provided with means for. establishing an operative relationshipbetween. said rotatable member and. said? electromagnetic means. only during preselected closely. succeeding 'opening'operations of said device, said. collapsible member being operable to cause said timing'mechanism to operate in unisonwithsaid rotatable member to delay operation ofsaid contacts during-close ing operations of said device. and; also. during.

saidpreselected opening operations .of said-means for opening saidv contacts when the value ofthe fault current is'below. a predeterminedamount, said collapsible member: being: collapsible: only in response to fault currents in excess-of said pre; determined value to: cause relativemovement-bee tween said rotatable member and said timin mechanism.

3. An. electric circuit reclosing' devicev for peli forming acycleof openingtand;closing operations and thereafter for automatically assuming. a locked open position; comprising; relatively moviablecontacts, current: responsive means, for op: erating saidi contacts, means. for. locking. said contacts: in the: open circuit: position, means; in?- cluding a ratchet wheel rotatablein. responseto preselected operations of said means for operating said contacts for causing operation of said means for lockingsaidcontacts-inthe open circuit position after. a predetermined numberof operations of said contacts during a. persistent fault condition, a timing mechanism. and yieldable biasing means interposed between said timing mechanism and said ratchet wheel and nor mally biasing said ratchet wheel into engagement with saidtiming mechanism, said biasing means being effective-to: cause said ratchetqwheel and said timing mechanism tomove in unison for opening forces developed by said means for operating said contacts which are below a predetermined magnitude, said biasing means being yieldable only in response to opening forces in excess of said predetermined magnitude to cause relative movement between said timing mechanism and said ratchet wheel.

4. An electric circuit reclosing device for performing a cycle of opening and closing operations and thereafter for automatically assuming a locked open position comprising relatively movable contacts, current responsive means for operating said contacts, means for locking said contacts in the open circuit position, means including a ratchet wheel rotatable in response to preselected operations of said means for operating said contacts for causing operation of said means for locking said contacts in the open circuit position after a predetermined number of operations of said contacts during a persistent fault condition, a projection on said ratchet wheel, a timing mechanism including a rotatable member, a projection on said rotatable member, and a precharged spring interposed between said ratchet wheel and said rotatable member and efiective normally to bias the projection on said 14 ratchet-.wheeland.onysaid. rotatablememben into engagement,- the. biasing farce exerted by: said spring being; sufiicient. to; maintain; said projections in engagement". andto. canse; said ratchet wheel and said rotatable. member; to rotate in unison when. the opening-force, exerted by said means for operating-said contacts-isbelowa pre. determined va1ue,-. the. biasing force. exerted by said springbeing insufficient toprevent relative movement between said ratchet wheel and; said rotatable memberwhen; the. opening force exerted-bysaid means; for operating saidcontacts is in. excess: of said predetermined value.

5. An. operating. mechanism for an-electric. circuits reclosingdevice having relatively movable contacts comprising; electromagnetic, means responsive to fault currents for: imparting opening movement to said'contactsmeans for imparting closing movement to. said .contacts, atiming mech anism, means includin -arotatablememberyand a precharged' collapsible member: connected. with said timing mechanismandjdisposed-in co.opera,.- tive relation to saidelectromagnetic means for interrelating-opening and closingsoperations of said contacts: with said timing. mechanism. said rotatable I member being: provided. with means for establishing an operative relationship between said'rotatable member and said electromagnetic means, only during preselected closely succeedingopening operationsof said device; said coltact's duringclosing operations of said device and also during aid preselected, openin operations of said'device when the value of thefault current is below a predetermined amount, said collapsible member. being collapsible. only. in, response to fault. currents, in excess, of, said predetermined valuetocause relative movement. between said rotatable member and said timing. mechanism, and meansoperable'in response. toa predetermined; angle of. rotation ofsaid rotatable member for. locking'said contacts in the, open circuit position.

6. An operating mechanismfor-an electric. circult. reclosing device having relatively; movable contacts comprising, meansresponsive to fault currents for opening said contacts, means for imparting closing movement to said contacts, a timing mechanism, a rotatable member, means movable by said means responsible to fault currents for operating said rotatable member in response to an opening operation of said device, means movable by said means for imparting closing movement to said contacts for operating said rotatable member upon closing movement of said contacts, a resilient member connecting said rotatable member with said timing mechanism, said resilient member permitting opening movement of said means for opening said contacts without affecting said timing mechanism when the fault current is in excess of a predetermined amount, said resilient member upon lesser fault currents being effective operably to connect the rotatable member with the timing mechanism for retarding substantially the full opening movement of said means for opening said contacts.

7. An operating mechanism for an electric circuit reclosing device having relatively movable contacts comprising, means responsive to fault currents for opening said contacts, means for imparting closing movement to said contacts, a

timing mechanism, a rotatable member, means movable by said means responsive to fault currents for operating said rotatable member upon closely succeeding preselected opening operations of said device, means movable by said means for imparting closing movement to said contacts for operating said rotatable member upon closing movement of said contacts, a resilient member connecting said rotatable member with said timing mechanism, said resilient member permitting at least a partial opening movement of said means for opening said contacts without affecting said timing mechanism when the fault current is in excess of a predetermined amount, said resilient member upon lesser fault currents being effective operably to connect the rotatable member with the timing mechanism for retarding substantially the full opening movement of said means for opening said contacts.

8. An operating mechanism for an electric circuit reclosing device having relatively movable contacts comprising first means responsive to fault currents for opening said contacts, second means for imparting closing movement to said contacts, a movable member, means responsive to an opening operation of said first means for moving said movable member, a timing mechanism, precharged resilient means interposed between said timing mechanism and said movable member, said resilient means being yieldable to render said timing mechanism ineffective to retard at least a portion of the opening movement of said first means when the fault current is in excess of a predetermined value, said resilient means remaining substantially nonyielding so as to cause operation of said timing mechanism to delay the opening operation of said first means in response to smaller fault currents.

9. An operating mechanism for an electric circuit reclosing device having relatively movable contacts comprising electromagnetic means for imparting opening movement to said contacts, relay means responsive to fault currents for initiating operation of said electromagnetic means, a ratchet wheel, an opening pawl movable in response to operation of said relay for rotating said ratchet wheel during preselected closely succeeding opening operations of said relay, a timing device, and resilient means interconnecting said A ratchet wheel and said timing device, said resilient means allowing full opening movement of said relay without causing appreciable operation of said timing device when the fault current is in excess of a predetermined amount, said resilient means being effective to cause operation of said timing device and delayed opening operation of said relay for a substantial portion of the opening operation of said relay when the fault current is less than said predetermined value.

10. An operating mechanism for an electric circuit reclosing device having relatively movable contacts comprising electromagnetic means for imparting opening movement to said contacts, relay means responsive to fault currents for initiating operation of said electromagnetic means, means for imparting closing movement to said contacts, a ratchet wheel, an opening pawl movable in response to operation of said relay for rotating said ratchet wheel during preselected closely succeeding opening operations of said relay, a closing pawl movable with a movable one of said contacts for rotating said ratchet wheel in response to closing movement of said contacts, a timing device, and resilient means interconnecting said ratchet wheel and said timing device, said resilient means allowing opening movement of said relay Without causing appreciable operation of said timing device when the fault current is in excess of a predetermined amount, said resilient means being effective to cause operation of said timing device and delayed open+ ing operation of said relay for a substantial portion of the opening operation of said relay when the fault current is less than said predetermined value.

ROBERT F. QUINN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,123,288 I-Iellmund Jan. 5, 1915 2,311,714 Thompson et al. Feb. 23, 1943 2,464,303 Gesellschap Mar. 15, 1949 2,487,025 Matthews Nov. 1, 1949 

